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Trying to add in a hydro power input to my existing solar system - help with Victron 250/60 settings

Stokie

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Feb 3, 2022
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For a few years we have been using a solar array, charging a BYD lithium battery box, running through an Easy Solar 48/3000/50 Multiplus.
Finally, my hydro system is ready for adding in to the existing system for the winter months, when there is less sun and plenty of water.

I was excited the other day when I got the power from my F&P washing machine motor pelton-driven generator up to just over 500W. Still not up to the calculated 1000W I'm expecting...

I had just reconfigured my water system to be more efficient. In hindsight, I should have re-measured the no-load generator output voltage again, as it had probably increased.
I limited the amps in the 250/60 controller to 10A, which allowed the pelton to spin at higher revs, higher voltage. Half a kilowatt was a lot better than the 35W I had been getting previously.

While it was running, I opened the bluetooth Victron Connect app for the 250/60 and changed a few settings. I selected Lithium Iron battery in the battery type, and as it was running at around 200V and 2.6A, I lowered the maximum amps to 5A. Suddenly, the turbine must have been unloaded, as the volts hit 260v and the system switched the load off.

The result was the entire system went down, including the BYD lithium battery box. Up and running again half an hour later, thankfully.

My question: Why did the system crash? Was it by choosing lithium battery as battery type for the 250/60 charge controller? Or was it by limiting the charging amps to 5A? If so, why would this make a difference, if it was only running 2.6A in the cable?
 
I could be not following but I believe your measurements of 200 volts and 2.6 amps is before SCC. I also think your batteries are 48 volts. So 50 volts x 5 amps is 250 watts. 200 volts x 2.6 amps is 520 watts. I think you unloaded the generator by going to 5 amps. How do you plan to control the over spinning when charging is complete. Wind turbine people use a restive load and a special charge controller I believe from reading.
 
I could be not following but I believe your measurements of 200 volts and 2.6 amps is before SCC. I also think your batteries are 48 volts. So 50 volts x 5 amps is 250 watts. 200 volts x 2.6 amps is 520 watts. I think you unloaded the generator by going to 5 amps. How do you plan to control the over spinning when charging is complete. Wind turbine people use a restive load and a special charge controller I believe from reading.
Thanks for your reply.
My batteries are 48V. I've set up the Easy Solar Multi (using Assistants) to send AC power to a load on the AC2 output when state of charge reaches 98%, and to switch off the AC2 outlet when batteries reach 85% SoC.

Are you suggesting the 5 Amp maximum amps I set could have actually been the amps going in to the battery, and not the amps coming in to the charge controller? If that's the case, it would explain the volts going up.

Do I need to manually sync the output voltages from the multiplus and the 250/60 charge controllers? Or by selecting Lithium Iron for battery type in both of them, would Victron set the same voltage automatically?
 
“I limited the amps in the 250/60 controller to 10A,”

This is a output parameter ( battery side) not input parameter (hydro/ solar side)
Going to 5 amps reduced the dynamic drag even at 56 volts x 5 amps is only 280 watts.
 
“I limited the amps in the 250/60 controller to 10A,”

This is a output parameter ( battery side) not input parameter (hydro/ solar side)
Going to 5 amps reduced the dynamic drag even at 56 volts x 5 amps is only 280 watts.
Thanks for the clarification. Is there a way of affecting the input amps or voltage, in order to achieve a more ideal charge rate?
Perhaps changing the battery parameters in the Victron Connect bluetooth app? Unless I use massive (extremely water-hungry) jets to drive my pelton wheel, the 250/60 controller bogs it down with high amps and low voltage, leaving it spinning too slowly, and with greater cable losses.
 
Thanks for the clarification. Is there a way of affecting the input amps or voltage, in order to achieve a more ideal charge rate?
Perhaps changing the battery parameters in the Victron Connect bluetooth app?

No. The MPPT does this itself by varying the charge current to find the maximum power voltage/current from the input. The only thing you can do is limit output. This item may not work for your application at all.

Unless I use massive (extremely water-hungry) jets to drive my pelton wheel, the 250/60 controller bogs it down with high amps and low voltage, leaving it spinning too slowly, and with greater cable losses.

If you think this setup should get 1000W, you should likely set it to around 1000W/56.8V = 18A and adjust down from there. See what happens.

I see a problem when you hit absorption voltage. As the MPPT reduces its output to maintain absorption voltage, it's going to unload the turbine and cause it to spin faster. I would expect a dump load is necessary to prevent the turbine from overspeed.

Have you considered a C-40 controller?


It has a built-in diversion function to consume the excess power you don't need for your batteries. You will need to supply the dump load, i.e., something like a 1000W resistor or heating element.
 
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